The invention relates to porcine retroviral sequences, peptides encoded by porcine retroviral sequences, and methods of using the porcine retroviral nucleic acids and peptides.
Advances in solid organ transplantation and a chronic shortage of suitable organ donors have made xenotransplantation an attractive alternative to the use of human allografts. However, the potential for introduction of a new group of infectious diseases from donor animals into the human population is a concern with the use of these methods.
The term applied to the natural acquisition by humans of infectious agents carried by other species is zoonosis. The transplantation of infection from nonhuman species into humans is best termed xe2x80x9cdirect zoonosisxe2x80x9d or xe2x80x9cxenosis.xe2x80x9d
Nonhuman primates and swine have been considered the main potential sources of organs for xenotransplantation (Niekrasz et al.,(1992) Transplant Proc 24:625; Starzl et al. (1993) Lancet 341:65; Murphy et al. (1970) Trans Proc 4:546; Brede and Murphy (1972) Primates Med 7:18; Cooper et al. In Xenotransplantation: The Transplantation of Organs and Tissues between Species, eds. Cooper et al. (1991) p. 457; R Y Calne (1970) Transplant Proc 2:550; H. Auchincloss, Jr. (1988) Transplantation 46:1; and Chiche et al. (1993) Transplantation 6:1418). The infectious disease issues for primates and swine are similar to those of human donors. The prevention of infection depends on the ability to predict, to recognize, and to prevent common infections in the immunocompromised transplantation recipient (Rubin et al. (1993) Antimicrob Agents Chemother 37:619). Because of the potential carriage by nonhuman primates of pathogens easily adopted to humans, ethical concerns, and the cost of maintaining large colonies of primates, other species have received consideration as organ donors (Brede and Murphy (1972) Primates Med 7:18; Van Der Riet et al. (1987) Transplant Proc 19:4069; Katler In Xenotransplantation: The Transplantation of Organs and Tissues between Species, eds. Cooper et al. (1991) p. 457; Metzger et al. (1981) J Immunol 127:769; McClure et al. (1987) Nature 330:487; Letvin et al. (1987) J Infect Dis 156:406; Castro et al. (1991) Virology 184:219; Benveniste and Todaro (1973) Proc Natl Acad Sci USA 70:3316; and Teich, in RNA Tumor viruses, eds. Weiss et. al. (1985) p. 25) The economic importance of swine and experience in studies of transplantation in the miniature swine model have allowed some of the potential pathogens associated with these animals to be defined (Niekrasz et al. (1992) Transplant Proc 24:625; Cooper et al. In Xenotransplantation: The Transplantation of Organs and Tissues between Species, eds. Cooper et al. (1991) 457; and Leman et al. (1992) Diseases of Swine, 7th ed. Ames, Iowa:Iowa State University). Miniature swine have received consideration as organ donors because of a number of features of the species. The structure and function of the main pig organs are comparable to those of man. Swine attain body weights and organ sizes adequate to the provision of organs for human use. Lastly, veterinarians and commercial breeders have developed approaches to creation of specific-pathogen-free (SPF) swine with the ability to eliminate known pathogens from breeding colonies (Alexander et al. (1980) Proc 6th Int Congr Pig Vet Soc, Copenhagen; Betts (1961) Vet Rec 73:1349; Betts et al. (1960) Vet Rec 72:461; Caldwell et al. (1959) J Am Vet Med Assoc 135:504; and Yong (1964) Adv Vet Sci 9:61).
Concern exists over the transfer of porcine retroviruses by xenotransplantation (Smith (1993) N Engl J Med328:141). Many of the unique properties of the retroviruses are due to the synthesis of a complementary DNA copy from the RNA template (by reverse transcriptase), and integration of this DNA into the host genome. The integrated retroviral copy (which is referred to as an endogenous copy or xe2x80x9cprovirusxe2x80x9d) can be transmitted via the germ line.
In general, the invention features a purified swine or miniature swine retroviral nucleic acid, e.g., a Tsukuba nucleic acid, a purified miniature swine retroviral nucleic acid sequence of SEQ ID NO:1 or its complement, SEQ ID NO:2 or its complement, or SEQ ID NO:3 or its complement, and methods of their use in detecting the presence of porcine, e.g., miniature swine, retroviral sequences.
In another aspect, the invention features a purified nucleic acid, e.g., a probe or primer, which can specifically hybridize with a purified swine or miniature swine retroviral genome, e.g., a Tsukuba genome, the sequence of SEQ ID NO:1 or its complement, SEQ ID NO:2 or its complement, or SEQ ID NO:3 or its complement.
In preferred embodiments the nucleic acid is other than the entire retroviral genome of SEQ ID NO:1 or its complement, SEQ ID NO:2 or its complement, or SEQ ID NO:3 or its complement, e.g., it is at least 1 nucleotide longer, or at least 1 nucleotide shorter, or differs in sequence at at least one position, e.g., the nucleic acid is a fragment of the sequence of SEQ ID NO:1 or its complement SEQ ID NO:2 or its complement, or SEQ ID NO:3 or its complement, or it includes sequence additional to that of SEQ ID NO:1, or its complement, SEQ ID NO:2 or its complement, or SEQ ID NO:3 or its complement.
In preferred embodiments, the nucleic acid has at least 60%, 70%, 72%, more preferably at least 85%, more preferably at least 90%, more preferably at least 95%, most preferably at least 98%, 99% or 100% sequence identity or homology with a sequence from SEQ ID NO:1 or its complement, SEQ ID NO:2 or its complement, or SEQ ID NO:3 or its complement.
In other embodiments: the sequence of the nucleic acid differs from the corresponding sequence of SEQ ID NO: 1 or its complement, SEQ ID NO:2 or its complement, or SEQ ID NO:3 or its complement, by 1, 2, 3, 4, or 5 base pairs; the sequence of the nucleic acid differs from the corresponding sequence of SEQ ID NO: 1 or its complement, SEQ ID NO:2 or its complement, or SEQ ID NO:3 or its complement, by at least 1, 2, 3, 4, or 5 base pairs but less than 6, 7, 8, 9, or 10 base pairs.
In other preferred embodiments: the nucleic acid is at least 10, more preferably at least 15, more preferably at least 20, most preferably at least 25, 30, 50, 100, 1000, 2000, 4000, 6000, or 8060 nucleotides in length; the nucleic acid is less than 15, more preferably less than 20, most preferably less than 25, 30, 50, 100, 1000, 2000, 4000, 6000, or 8060 nucleotides in length.
In yet other preferred embodiments: the nucleic acid can specifically hybridize with a translatable region of a miniature swine retroviral genome, e.g., the retroviral genome of SEQ ID NO: 1, or its complement, SEQ ID NO:2 or its complement, or SEQ ID NO:3 or its complement, e.g., a region from the gag, pol, or env gene; the probe or primer can specifically hybridize with an untranslated region of a miniature swine retroviral genome, e.g., the retroviral genome of SEQ ID NO: 1, or its complement SEQ ID NO:2 or its complement, or SEQ ID NO:3 or its complement; the probe or primer can specifically hybridize with a non-conserved region of a miniature swine retroviral genome, e.g., the retroviral genome of SEQ ID NO: 1, or its complement, SEQ ID NO:2 or its complement, or SEQ ID NO:3 or its complement; the probe or primer can specifically hybridize with the highly conserved regions of a miniature swine retroviral genome, e.g., the retroviral genome of SEQ ID NO: 1, or its complement, SEQ ID NO:2 or its complement, or SEQ ID NO:3 or its complement.
In preferred embodiments, the primer is selected from the group consisting of SEQ ID NOs:4-74.
In preferred embodiments, hybridization of the probe to retroviral sequences can be detected by standard methods, e.g., by radiolabeled probes or by probes bearing nonradioactive markers such as enzymes or antibody binding sites. For example, a probe can be conjugated with an enzyme such as horseradish peroxidase, where the enzymatic activity of the conjugated enzyme is used as a signal for hybridization. Alternatively, the probe can be coupled to an epitope recognized by an antibody, e.g., an antibody conjugated to an enzyme or another marker.
In another aspect, the invention features a reaction mixture which includes a target nucleic acid, e.g., a human, swine or a miniature swine nucleic acid, and a purified second nucleic acid, e.g., a probe or primer, as, e.g., is described herein, which specifically hybridizes with the sequence of SEQ ID NO:1 or its complement, SEQ ID NO:2 or its complement, or SEQ ID NO:3 or its complement, a swine or a miniature swine retroviral nucleic acid, e.g., a Tsukuba nucleic acid.
In preferred embodiments, the target nucleic acid includes RNA; or includes DNA.
In preferred embodiments, the target nucleic acid includes: genomic DNA isolated from a miniature swine; RNA or cDNA, e.g., cDNA made from an RNA template, isolated from a miniature swine; DNA, RNA or cDNA, e.g., cDNA made from an RNA template, isolated from a miniature swine organ, e.g., a kidney; RNA, DNA or cDNA, e.g., cDNA made from an RNA template, isolated from a miniature swine potential donor organ, RNA, DNA or cDNA, e.g., cDNA made from an RNA template, isolated from a miniature swine organ which has been transplanted into a organ recipient, e.g., a xenogeneic recipient, e.g., a primate, e.g., a human.
In preferred embodiments, the target nucleic acid includes: genomic DNA isolated from a swine; RNA or cDNA, e.g., cDNA made from an RNA template, isolated from a swine; DNA, RNA or cDNA, e.g., cDNA made from an RNA template, isolated from a swine organ, e.g., a kidney; RNA, DNA or cDNA, e.g., cDNA made from an RNA template, isolated from a swine potential donor organ; RNA, DNA or cDNA, e.g., cDNA made from an RNA template, isolated from a swine organ which has been transplanted into a organ recipient, e.g., a xenogeneic recipient, e.g., a primate, e.g., a human.
In a preferred embodiment: the second nucleic acid is a porcine retroviral sequence, probe or primer, e.g., as described herein, e.g., a Tsukuba-1 retroviral sequence the second nucleic acid is a sequence of SEQ ID NO:1 or its complement, SEQ ID NO:2 or its complement, or SEQ ID NO:3 or its complement, or a fragment of the sequence or complement at least 10, 20, or 30, basepairs in length.
In preferred embodiments, the second nucleic acid has at least 60%, 70%, 72%, more preferably at least 85%, more preferably at least 90%, more preferably at least 95%, most preferably at least 98%, 99% or 100% sequence identity or homology with a sequence from SEQ ID NO:1 or its complement, SEQ ID NO:2 or its complement, or SEQ ID NO:3 or its complement.
In other preferred embodiments: the second nucleic acid is at least 10, more preferably at least 15, more preferably at least 20, most preferably at least 25, 30, 50, 100, 1000, 2000, 4000, 6000, or 8060 nucleotides in length; the nucleic acid is less than 15, more preferably less than 20, most preferably less than 25, 30, 50, 100, 1000, 2000, 4000, 6000, or 8060 nucleotides in length; the second nucleic acid is a full length retroviral genome.
In preferred embodiments the second nucleic acid is: a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence which encodes a gag protein; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence from nucleotides 2452-4839 (e.g, from nucleotides 3112-4683) of SEQ ID NO:1, nucleotides 598-2169 (e.g, from nucleotides 598-2169) of SEQ ID NO:2, or nucleotides 585-2156 (e.g, from nucleotides 585-2156) of SEQ ID NO:3, or naturally occurring mutants thereof;
a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence which encodes a pol protein; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence from nucleotides 4871-8060 of SEQ ID NO:1, nucleotides 2320-4737 of SEQ ID NO:2, or nucleotides 2307-5741 of SEQ ID NO:3, or naturally occurring mutants hereof; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence which encodes a env protein; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence from nucleotides 2-1999 (e.g, from nucleotides 86-1999) of SEQ ID NO:1, nucleotides 4738-6722 (e.g, from nucleotides 4738-6722) of SEQ ID NO:2, or nucleotides 5620-7533 of SEQ ID NO:3, or naturally occurring mutants thereof.
In another aspect, the invention features a method for screening a cell or a tissue, e.g., a cellular or tissue transplant, e.g., a xenograft, for the presence or expression of a swine or a miniature swine retrovirus or retroviral sequence, e.g., an endogenous miniature swine retrovirus. The method includes:
contacting a target nucleic acid from the tissue with a second sequence chosen from the group of: a sequence which can specifically hybridize to a porcine retroviral sequence; a sequence which can specifically hybridize to the sequence of SEQ ID NO:1 or its complement; a sequence which can specifically hybridize to the sequence of SEQ ID NO:2 or its complement; a sequence which can specifically hybridize to the sequence of SEQ ID NO:3 or its complement; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence which encodes a gag protein; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence from nucleotides 2452-4839 (e.g, from nucleotides 3112-4683) of SEQ ID.NO:1, nucleotides 598-2169 (e.g, from nucleotides 598-2169) of SEQ ID NO:2, or nucleotides 585-2156 (e.g, from nucleotides 585-2156) of SEQ ID NO:3, or naturally occurring mutants thereof; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence which encodes a pol protein; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence from nucleotides 4871-8060 of SEQ ID NO:1, nucleotides 2320-4737 of SEQ ID NO:2, or nucleotides 2307-5741 of SEQ ID NO:3, or naturally occurring mutants thereof, a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence which encodes a env protein; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence from nucleotides 2-1999 (e.g, from nucleotides 86-1999) of SEQ ID NO:1, nucleotides 4738-6722 (e.g, from nucleotides 4738-6722) of SEQ ID NO:2, or nucleotides 5620-7533 of SEQ ID NO:3, or naturally occurring mutants thereof; a swine or miniature swine retroviral nucleic acid; or a Tsukuba nucleic acid under conditions in which hybridization can occur, hybridization being indicative of the presence or expression of an endogenous miniature swine retrovirus or retroviral sequence in the tissue or an endogenous swine retrovirus in the tissue.
In preferred embodiments, the method further includes amplifying the target nucleic acid with primers which specifically hybridize to the sequence of SEQ ID NO:1 or its complement, SEQ ID NO:2 or its complement, or SEQ ID NO:3 or its complement.
In preferred embodiments, the tissue or cellular transplant is selected from the group consisting of: heart, lung, liver, bone marrow, kidney, brain cells, neural tissue, pancreas or pancreatic cells, thymus, or intestinal tissue.
In other preferred embodiments, the target nucleic acid is: DNA; RNA; or cDNA.
In other preferred embodiments, the target nucleic acid is taken from: a tissue sample, or a blood sample, e.g., a tissue biopsy sample, e.g., a tissue sample suitable for in situ hybridization or immunohistochemistry.
In preferred embodiments, the target nucleic acid includes: genomic DNA isolated from a miniature swine; RNA or cDNA, e.g., cDNA made from an RNA template, isolated from a miniature swine; DNA, RNA or cDNA, e.g., cDNA made from an RNA template, isolated from a miniature swine organ, e.g., a kidney; RNA, DNA or cDNA, e.g., cDNA made from an RNA template, isolated from a miniature swine potential donor organ; RNA, DNA or cDNA, e.g., cDNA made from an RNA template, isolated from a miniature swine organ which has been transplanted into a organ recipient, e.g., a xenogeneic recipient, e.g., a primate, e.g., a human.
In preferred embodiments, the target nucleic acid includes: genomic DNA isolated from a swine; RNA or cDNA, e.g., cDNA made from an RNA template, isolated from a swine; DNA, RNA or cDNA, e.g., cDNA made from an RNA template, isolated from a swine organ, e.g., a kidney; RNA, DNA or cDNA, e.g., cDNA made from an RNA template, isolated from a swine potential donor organ; RNA, DNA or cDNA, e.g., cDNA made from an RNA template, isolated from a swine organ which has been transplanted into a organ recipient, e.g., a recipient swine or a xenogeneic recipient, e.g., a primate, e.g., a human.
In a preferred embodiment the target nucleic acid is RNA, or a nucleic acid amplified from RNA in the tissue, and hybridization is correlated with expression of an endogenous miniature swine retrovirus or retroviral sequence or an endogenous swine retrovirus.
In a preferred embodiment the target nucleic acid is DNA, or a nucleic acid amplified from DNA in the tissue, and hybridization is correlated with the presence of an endogenous miniature swine retrovirus or an endogenous swine retrovirus.
In preferred embodiments, the second nucleic acid has at least 60%, 70%, 72%, more preferably at least 85%, more preferably at least 90%, more preferably at least 95%, most preferably at least 98%, 99% or 100% sequence identity or homology with a sequence from SEQ ID NO:1 or its complement, SEQ ID NO:2 or its complement, or SEQ ID NO:3 or its complement.
In other preferred embodiments: the second nucleic acid is at least 10, more preferably at least 15, more preferably at least 20, most preferably at least 25, 30, 50, 100, 1000, 2000, 4000, 6000, or 8060 nucleotides in length; the nucleic acid is less than 15, more preferably less than 20, most preferably less than 25, 30, 50, 100, 1000, 2000, 4000, 6000, or 8060 nucleotides in length; the second nucleic acid is a full length retroviral genome.
In another aspect, the invention features a method of screening a porcine derived cell or tissue for the presence of an activatable porcine retrovirus, e.g., an activatable porcine provirus. The method includes:
stimulating a porcine derived cell or tissue with a treatment which can activate a retrovirus;
contacting a target nucleic acid from the porcine derived cell or tissue with a second sequence chosen from the group of: a sequence which can specifically hybridize to a porcine retroviral sequence; a sequence which can specifically hybridize to the sequence of SEQ ID NO:1 or its complement; a sequence which can specifically hybridize to the sequence of SEQ ID NO:2 or its complement; a sequence which can specifically hybridize to the sequence of SEQ ID NO:3 or its complement; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence which encodes a gag protein; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence from nucleotides 2452-4839 (e.g. from nucleotides 3112-4683) of SEQ ID NO:1, nucleotides 598-2169 (e.g, from nucleotides 598-2169) of SEQ ID NO:2, or nucleotides 585-2156 (e.g, from nucleotides 585-2156) of SEQ ID NO:3, or naturally occurring mutants thereof; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence which encodes a pol protein; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence from nucleotides 4871-8060 of SEQ ID NO:1, nucleotides 2320-4737 of SEQ ID NO:2, or nucleotides 2307-5741 of SEQ ID NO:3, or naturally occurring mutants thereof; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence which encodes a env protein; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence from nucleotides 2-1999 (e.g; from nucleotides 86-1999) of SEQ ID NO:1, nucleotides 4738-6722 (e.g. from nucleotides 4738-6722) of SEQ ID NO:2, or nucleotides 5620-7533 of SEQ ID NO:3, or naturally occurring mutants thereof; a swine or miniature swine retroviral nucleic acid; or a Tsukuba nucleic acid hybridization being indicative of the presence of an activatable porcine provirus in the porcine derived cell or tissue.
In preferred embodiments the treatment is: contact with a drug, e.g., a steroid or a cytotoxic agent, infection or contact with a virus, the induction of stress, e.g., nutritional stress or immunologic stress, e.g., contact with a T-cell, e.g., a reactive T-cell.
In preferred embodiments, the method further includes amplifying the target nucleic acid with primers which specifically hybridize to the sequence of SEQ ID NO:1 or its complement, SEQ ID NO:2 or its complement, or SEQ ID NO:3 or its complement.
In other preferred embodiments, the target nucleic acid is taken from: a tissue sample, or a blood sample, e.g., a tissue biopsy sample, e.g., a tissue sample suitable for in situ hybridization or immunohistochemistry.
In preferred embodiments, the target nucleic acid includes: genomic DNA isolated from a miniature swine; RNA or cDNA, e.g., cDNA made from an RNA template, isolated from a miniature swine; DNA, RNA or cDNA, e.g., cDNA made from an RNA template, isolated from a miniature swine organ, e.g., a kidney; RNA, DNA or cDNA, e.g., cDNA made from an RNA template, isolated from a miniature swine potential donor organ; RNA, DNA or cDNA, e.g., cDNA made from an RNA template, isolated from a miniature swine organ which has been transplanted into a organ recipient, e.g., a xenogeneic recipient, e.g., a primate, e.g., a human.
In preferred embodiments, the target nucleic acid includes: genomic DNA isolated from a swine; RNA or cDNA, e.g., cDNA made from an RNA template, isolated from a swine; DNA, RNA or cDNA, e.g., cDNA made from an RNA template, isolated from a swine organ, e.g., a kidney; RNA, DNA or cDNA, e.g., cDNA made from an RNA template, isolated from a swine potential donor organ; RNA, DNA or cDNA, e.g., cDNA made from an RNA template, isolated from a swine organ which has been transplanted into a organ recipient, e.g., a recipient swine or a xenogeneic recipient, e.g., a primate, e.g., a human.
In preferred embodiments, the second nucleic acid has at least 60%, 70%, 72%, more preferably at least 85%, more preferably at least 90%; more preferably at least 95%, most preferably at least 98%, 99% or 100% sequence identity or homology with a sequence from SEQ ID NO:1 or its complement, SEQ ID NO:2 or its complement, or SEQ ID NO:3 or its complement.
In other preferred embodiments: the second nucleic acid is at least 10, more preferably at least 15, more preferably at least 20, most preferably at least 25, 30, 50, 100, 1000, 2000, 4000, 6000, or 8060 nucleotides in length; the nucleic acid is less than 15, more preferably less than 20, most preferably less than 25, 30, 50, 100, 1000, 2000, 4000, 6000, or 8060 nucleotides in length; the second nucleic acid is a full length retroviral genome.
In another aspect, the invention features a method for screening a miniature swine genome or a swine genome for the presence of a porcine retrovirus or retroviral sequence, e.g., an endogenous porcine retrovirus. The method includes:
contacting the miniature swine (or swine) genomic DNA with a second sequence chosen from the group of: a sequence which can specifically hybridize to a porcine retroviral sequence; a sequence which can specifically hybridize to the sequence of SEQ ID NO:1 or its complement; a sequence which can specifically hybridize to the sequence of SEQ ID NO:2 or its complement; a sequence which can specifically hybridize to the sequence of SEQ ID NO:3 or its complement; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence which encodes a gag protein; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence from nucleotides 2452-4839 (e.g, from nucleotides 3112-4683) of SEQ ID NO:1, nucleotides 598-2169 (e.g, from nucleotides 598-2169) of SEQ ID NO:2, or nucleotides 585-2156 (e.g, from nucleotides 585-2156) of SEQ ID NO:3, or naturally occurring mutants thereof; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence which encodes a pol protein; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence from nucleotides 4871-8060 of SEQ ID NO:1, nucleotides 2320-4737 of SEQ ID NO:2, or nucleotides 2307-5741 of SEQ ID NO:3, or naturally occurring mutants thereof; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence which encodes a env protein; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence from nucleotides 2-1999 (e.g, from nucleotides 86-1999) of SEQ ID NO:1, nucleotides 4738-6722 (e.g, from nucleotides 4738-6722) of SEQ ID NO:2, or nucleotides 5620-7533 of SEQ ID NO:3, or naturally occurring mutants thereof; a swine or miniature swine retroviral nucleic acid; or a Tsukuba nucleic acid under conditions in which the sequences can hybridize, hybridization being indicative of the presence of the endogenous porcine retrovirus or retroviral sequence in the miniature swine (or swine) genome.
In preferred embodiments, the method further includes amplifying all or a portion of the miniature swine (or swine) genome with primers which specifically hybridize to the sequence of SEQ ID NO:1 or its complement, SEQ ID NO:2 or its complement, or SEQ ID NO:3 or its complement.
In a preferred embodiment: the second nucleic acid is a porcine retroviral sequence, probe or primer, e.g., as described herein, e.g., a Tsukuba-1 retroviral sequence; the second nucleic acid is a sequence of SEQ ID NO:1 or its complement, SEQ ID NO:2 or its complement, or SEQ ID NO:3 or its complement, or a fragment of the sequence or complement at least 10, 20, or 30, basepairs in length.
In preferred embodiments, the second nucleic acid has at least 60%, 70%, 72%, more preferably at least 85%, more preferably at least 90%, more preferably at least 95%, most preferably at least 98%, 99% or 100% sequence identity or homology with a sequence from SEQ ID NO:1 or its complement, SEQ ID NO:2 or its complement, or SEQ ID NO:3 or its complement.
In other preferred embodiments: the second nucleic acid is at least 10, more preferably at least 15, more preferably at least 20, most preferably at,least 25, 30, 50, 100, 1000, 2000, 4000, 6000, or 8060 nucleotides in length; the nucleic acid is less than 15, more preferably less than 20, most preferably less than 25, 30, 50, 100, 1000, 2000, 4000, 6000, or 8060 nucleotides in length; the second nucleic acid is a full length retroviral genome.
In another aspect, the invention features a method for screening a genetically modified miniature swine or a genetically modified swine for the presence or expression of a miniature swine or swine retrovirus or retroviral sequence, e.g., an endogenous miniature swine retrovirus. The method includes:
contacting a target nucleic acid from the genetically modified miniature swine or swine with a second sequence chosen from the group of: a sequence which can specifically hybridize to a porcine retroviral sequence; a sequence which can specifically hybridize to the sequence of SEQ ID NO:1 or its complement; a sequence which can specifically hybridize to the sequence of SEQ ID NO:2 or its complement; a sequence which can specifically hybridize to the sequence of SEQ ID NO:3 or its complement; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence which encodes a gag protein; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence from nucleotides 2452-4839 (e.g, from nucleotides 3112-4683) of SEQ ID NO:1, nucleotides 598-2169 (e.g, from nucleotides 598-2169) of SEQ ID NO:2, or nucleotides 585-2156 (e.g, from nucleotides 585-2156) of SEQ ID NO:3, or naturally occurring mutants thereof;
a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence which encodes a pol protein; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence from nucleotides 4871-8060 of SEQ ID NO:1, nucleotides 2320-4737 of SEQ ID NO:2, or nucleotides 2307-5741 of SEQ ID NO:3, or naturally occurring mutants thereof; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence which encodes a env protein; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence from nucleotides 2-1999 (e.g, from nucleotides 86-1999) of SEQ ID NO:1, nucleotides 4738-6722 (e.g, from nucleotides 4738-6722) of SEQ ID NO:2, or nucleotides 5620-7533 of SEQ ID NO:3, or naturally occurring mutants thereof; a swine or miniature swine retroviral nucleic acid; or a Tsukuba nucleic acid under conditions in which hybridization can occur, hybridization being indicative of the presence or expression of an endogenous miniature swine retrovirus or retroviral sequence or swine retrovirus or retroviral sequence in the genetically modified miniature swine or swine.
In preferred embodiments, the method further includes amplifying the target nucleic acid with primers which specifically hybridize to the sequence of SEQ ID NO:1 or its complement, SEQ ID NO:2 or its complement, or SEQ ID NO:3 or its complement.
In preferred embodiments, the target nucleic acid includes: genomic DNA isolated from a miniature swine; RNA or cDNA, e.g., cDNA made from an RNA template, isolated from a miniature swine; DNA, RNA or cDNA, e.g., cDNA made from an RNA template, isolated from a miniature swine organ, e.g., a kidney; RNA, DNA or cDNA, e.g., cDNA made from an RNA template, isolated from a miniature swine potential donor organ; RNA, DNA or cDNA, e.g., cDNA made from an RNA template, isolated from a miniature swine organ which has been transplanted into a organ recipient, e.g., a xenogeneic recipient, e.g., a primate, e.g., a human.
In preferred embodiments, the target nucleic acid includes: genomic DNA isolated from a swine; RNA or cDNA, e.g., cDNA made from an RNA template, isolated from a swine; DNA, RNA or cDNA, e.g., cDNA made from an RNA template, isolated from a swine organ, e.g., a kidney; RNA, DNA or cDNA, e.g., cDNA made from an RNA template, isolated from a swine potential donor organ; RNA, DNA or cDNA, e.g., cDNA made from an RNA template, isolated from a swine organ which has been transplanted into a organ recipient, e.g., a recipient swine or a xenogeneic recipient, e.g., a primate, e.g., a human.
In preferred embodiments, the second nucleic acid has at least 60%, 70%, 72%, more preferably at least 85%, more preferably at least 90%, more preferably at least 95%, most preferably at least 98%, 99% or 100% sequence identity or homology with a sequence from SEQ ID NO:1 or its complement, SEQ ID NO:2 or its complement, or SEQ ID NO:3 or its complement.
In other preferred embodiments: the second nucleic acid is at least 10, more preferably at least 15, more preferably at least 20, most preferably at least 25, 30, 50, 100, 1000, 2000, 4000, 6000, or 8060 nucleotides in length; the nucleic acid is less than 15, more preferably less than 20, most preferably less than 25, 30, 50, 100, 1000, 2000, 4000, 6000, or 8060 nucleotides in length; the second nucleic acid is a full length retroviral genome.
In another aspect, the invention features a method of assessing the potential risk associated with the transplantation of a graft from a donor miniature swine or swine into a recipient animal, e.g., a miniature swine or swine, a non-human primate, or a human. The method includes:
contacting a target nucleic acid from the donor, recipient or the graft, with a second sequence chosen from the group of: a nucleic acid sequence which specifically hybridizes a sequence which can specifically hybridize to a porcine retroviral sequence; a sequence which can specifically hybridize to the sequence of SEQ ID NO:1 or its complement; a sequence which can specifically hybridize to the sequence of SEQ ID NO:2 or its complement; a sequence which can specifically hybridize to the sequence of SEQ ID NO:3 or its complement; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence which encodes a gag protein; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence from nucleotides 2452-4839 (e.g, from nucleotides 3112-4683) of SEQ ID NO:1, nucleotides 598-2169 (e.g, from nucleotides 598-2169) of SEQ ID NO:2, or nucleotides 585-2156 (e.g, from nucleotides 585-2156) of SEQ ID NO:3, or naturally occurring mutants thereof;
a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence which encodes a pol protein; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence from nucleotides 4871-8060 of SEQ ID NO:1, nucleotides 2320-4737 of SEQ ID NO:2, or nucleotides 2307-5741 of SEQ ID NO:3, or naturally occurring mutants thereof;
a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence which encodes a env protein; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence from nucleotides 2-1999 (e.g, from nucleotides 86-1999) of SEQ ID NO:1, nucleotides 4738-6722 (e.g, from nucleotides 4738-6722) of SEQ ID NO:2, or nucleotides 5620-7533 of SEQ ID NO:3, or naturally occurring mutants thereof; a swine or miniature swine retroviral nucleic acid; or a Tsukuba nucleic acid under conditions in which the sequences can hybridize, hybridization being indicative of a risk associated with the transplantation.
In a preferred embodiment: the second nucleic acid is a Tsukuba-1 retroviral sequence, probe or primer, e.g., as described herein; the second nucleic acid is a porcine retroviral sequence, probe or primer, e.g., as described herein; the second nucleic acid is the sequence of SEQ ID NO:1 or its complement, SEQ ID NO:2 or its complement, or SEQ ID NO:3 or its complement, or a fragment of the sequence or complement at least 10, 20, or 30, basepairs in length.
In preferred embodiments, the target nucleic acid includes: genomic DNA isolated from a miniature swine; RNA or cDNA, e.g., cDNA made from an RNA template, isolated from a miniature swine; DNA, RNA or cDNA, e.g., cDNA made from an RNA template, isolated from a miniature swine organ, e.g., a kidney; RNA, DNA or cDNA, e.g., cDNA made from an RNA template, isolated from a miniature swine potential donor organ; RNA, DNA or cDNA, e.g., cDNA made from an RNA template, isolated from a miniature swine organ which has been transplanted into a organ recipient, e.g.,a xenogeneic recipient, e.g., a primate, e.g., a human.
In preferred embodiments, the target nucleic acid includes: genomic DNA isolated from a swine; RNA or cDNA, e.g., cDNA made from an RNA template, isolated from a swine; DNA, RNA or cDNA, e.g., cDNA made from an RNA template, isolated from a swine organ, e.g., a kidney; RNA, DNA or cDNA, e.g., cDNA made from an RNA template, isolated from a swine potential donor organ; RNA, DNA or cDNA, e.g., cDNA made from an RNA template, isolated from a swine organ which has been transplanted into a organ recipient, e.g., a recipient swine or a xenogeneic recipient, e.g., a primate, e.g., a human.
In preferred embodiments, the second nucleic acid has at least 60%, 70%, 72%, more preferably at least 85%, more preferably at least 90%, more preferably at least 95%, most preferably at least 98%, 99% or 100% sequence identity or homology with a sequence from SEQ ID NO:1 or its complement, SEQ ID NO:2 or its complement, or SEQ ID NO:3 or its complement.
In other preferred embodiments: the second nucleic acid is at least 10, more preferably at least 15, more preferably at least 20, most preferably at least 25, 30, 50, 100, 1000, 2000, 4000, 6000, or 8060 nucleotides in length; the nucleic acid is less than 15, more preferably less than 20, most preferably less than 25, 30, 50, 100, 1000, 2000, 4000, 6000, or 8060 nucleotides in length; the second nucleic acid is a full length retroviral genome.
In another aspect, the invention features a method of determining if an endogenous miniature swine or swine retrovirus or retroviral sequence genome includes a mutation which modulates its expression, e.g., results in misexpression. The method includes:
determining the structure of the endogenous retroviral genome, and
comparing the structure of the endogenous retroviral genome with the retroviral sequence of SEQ ID NO:1 or its complement, SEQ ID NO:2 or its complement, or SEQ ID NO:3 or its complement, a difference being predictive of a mutation.
In preferred embodiments the method includes sequencing the endogenous genome and comparing it with a sequence from SEQ ID NO:1 or its complement, SEQ ID NO:2 or its complement, or SEQ ID NO:3 or its complement.
In preferred embodiments, the method includes using primers to amplify, e.g., by PCR, LCR (ligase chain reaction), or other amplification methods, a region of the endogenous retroviral genome, and comparing the structure of the amplification product to he sequence of SEQ ID NO:1 or its complement, SEQ ID NO:2 or its complement, or SEQ ID NO:3 or its complement to determine if there is difference in sequence between retroviral genome and SEQ ID NO:1 or its complement, SEQ ID NO:2 or its complement, or SEQ ID NO:3 or its complement. The method further includes determining if one or more restriction sites exist in the endogenous retroviral genome, and determining if the sites exist in SEQ ID NO:1 or its complement, SEQ ID NO:2 or its complement, or SEQ ID NO:3 or its complement.
In preferred embodiments, the mutation is a gross defect, e.g., an insertion, inversion, translocation or a deletion, of all or part of the retroviral genome.
In preferred embodiments, detecting the mutation can include: (i) providing a labeled PCR probe amplified from DNA (e.g., SEQ ID NO: 1, SEQ ID NO: 2, or SEQ ID NO: 3) containing a porcine retroviral nucleotide sequence which hybridizes to a sense or antisense sequence from the porcine retroviral genome (e.g., SEQ ID NO: 1, SEQ ID NO: 2, or SEQ ID NO: 3), or naturally occurring mutants thereof; (ii) exposing the probe/primer to nucleic acid of the tissue (e.g., genomic DNA) digested with a restriction endonuclease; and (iii) detecting by in situ hybridization of the probe/primer to the nucleic acid, the presence or absence of the genetic lesion. Alternatively, direct PCR analysis, using primers specific for porcine retroviral genes (e.g., genes comprising the nucleotide sequence shown in SEQ ID NO: 1, SEQ ID NO: 2, or SEQ ID NO: 3), can be used to detect the presence or absence of the genetic lesion in the porcine retroviral genome by comparing the products amplified.
In another aspect, the invention features a method of providing a miniature swine or a swine free of an endogenous retrovirus or retroviral sequence, e.g., activatable retrovirus, insertion at a preselected site. The method includes:
performing a breeding cross between a first miniature swine (or swine) having a retroviral insertion at the preselected site and a second miniature swine (or swine) not having a retroviral insertion at a preselected site, e.g., the same site, and recovering a progeny miniature swine (or swine), not having the insertion, wherein the presence or absence of the retroviral insertion is determined by contacting the genome of a miniature swine(or swine) with a sequence which can specifically hybridize to a porcine retroviral sequence; a sequence which can specifically hybridize to the sequence of SEQ ID NO:1 or its complement; a sequence which can specifically hybridize to the sequence of SEQ ID NO:2 or its complement; a sequence which can specifically hybridize to the sequence of SEQ ID NO:3 or its complement; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence which encodes a gag protein; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence from nucleotides 2452-4839 (e.g, from nucleotides 3112-4683) of SEQ ID NO:1, nucleotides 598-2169 (e.g, from nucleotides 598-2169) of SEQ ID NO:2, or nucleotides 585-2156 (e.g, from nucleotides 585-2156) of SEQ ID NO:3, or naturally occurring mutants thereof;
a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence which encodes a pol protein; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence from nucleotides 4871-8060 of SEQ ID NO:1, nucleotides 2320-4737 of SEQ ID NO:2, or nucleotides 2307-5741 of SEQ ID NO:3, or naturally occurring mutants thereof; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence which encodes a env protein; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence from nucleotides 2-1999 (e.g, from nucleotides 86-1999) of SEQ ID NO:1, nucleotides 4738-6722 (e.g, from nucleotides 4738-6722) of SEQ ID NO:2, or nucleotides 5620-7533 of SEQ ID NO:3, or naturally occurring mutants thereof; a swine or miniature swine retroviral nucleic acid; or a Tsukuba nucleic acid.
In preferred embodiments, the nucleic acid is hybridized to nucleic acid, e.g., DNA from the genome, of the first animal or one of its ancestors.
In preferred embodiments, the nucleic acid is hybridized to nucleic acid, e.g., DNA from the genome, of the second animal or one of its ancestors.
In preferred embodiments, the nucleic acid is hybridized to nucleic acid, e.g., DNA from the genome, of the progeny animal or one of its descendants.
In preferred embodiments, the nucleic acid has at least 60%, 70%, 72%, more preferably at least 85%, more preferably at least 90%, more preferably at least 95%, most preferably at least 98%, 99% or 100% sequence identity or homology with a sequence from SEQ ID NO:1 or its complement, SEQ ID NO:2 or its complement, or SEQ ID NO:3 or its complement.
In other preferred embodiments: the nucleic acid is at least 10, more preferably at least 15, more preferably at least 20, most preferably at least 25, 30, 50, 100, 1000, 2000, 4000, 6000, or 8060 nucleotides in length; the nucleic acid is less than 15, more preferably less than 20, most preferably less than 25, 30, 50, 100, 1000, 2000, 4000, 6000, or 8060 nucleotides in length; the nucleic acid is a full length retroviral genome.
In another aspect, the invention features a method of evaluating a treatment, e.g., an immunosuppressive treatment, for the ability to activate a retrovirus, e.g., an endogenous porcine retrovirus. The method includes:
administering a treatment to a subject, e.g., a miniature swine (or a swine), having an endogenous porcine retrovirus; and
detecting expression of the porcine retrovirus with a purified nucleic acid sequence which specifically hybridizes to the sequence of SEQ ID NO:1 or its complement, SEQ ID NO:2 or its complement, or SEQ ID NO:3 or its complement.
In preferred embodiments, the immunosuppresive treatment includes radiation, chemotherapy or drug treatment.
In preferred embodiments: the treatment is one which can induce immunological tolerance; the treatment is one which can introduce new genetic material, e.g., introduce new genetic material into a miniature swine genome (or a swine genome) or into the genome of a host which receives a swine or a miniature swine graft, e.g., the treatment is one which introduces a new genetic material via retroviral mediated transfer.
In a preferred embodiment: the purified nucleic acid is a Tsukuba-1 retroviral sequence, probe or primer, e.g., as described herein; the purified nucleic acid is a porcine: retroviral sequence, probe or primer, e.g., as described herein; the purified nucleic acid is the sequence of SEQ ID NO:1 or its complement, SEQ ID NO:2 or its complement, or SEQ ID NO:3 or its complement, or a fragment of such sequence or complement at least 10, 20, or 30, basepairs in length.
In preferred embodiments, the purified nucleic acid has at least 60%, 70%, 72%, more preferably at least 85%, more preferably at least 90%, more preferably at least 95%, most preferably at least 98%, 99% or 100% sequence identity or homology with a sequence from SEQ ID NO:1 or its complement, SEQ ID NO:2 or its complement, or SEQ ID NO:3 or its complement.
In other preferred embodiments: the purified nucleic acid is at least 10, more preferably at least 15, more preferably at least 20, most preferably at least 25, 30, 50, 100. 1000, 2000, 4000, 6000, or 8060 nucleotides in length; the nucleic acid is less than 15, more preferably less than 20, most preferably less than 25, 30, 50, 100, 1000, 2000, 4000, 6000, or 8060 nucleotides in length; the purified nucleic acid is a full length retroviral genome.
In preferred embodiments the second nucleic acid is: a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence which encodes a gag protein; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence from nucleotides 2452-4839 (e.g, from nucleotides 3112-4683) of SEQ ID NO:1, nucleotides 598-2169 (e.g, from nucleotides 598-2169) of SEQ ID NO:2, or nucleotides 585-2156 (e.g, from nucleotides 585-2156) of SEQ ID NO:3, or naturally occurring mutants thereof; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence which encodes a pol protein; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence from nucleotides 4871-8060 of SEQ ID NO:1, nucleotides 2320-4737 of SEQ ID NO:2, or nucleotides 2307-5741 of SEQ ID NO:3, or naturally occurring mutants thereof; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence which encodes a env protein; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence from nucleotides 2-1999 (e.g, from nucleotides 86-1999) of SEQ ID NO:1, nucleotides 4738-6722 (e.g, from nucleotides 4738-6722) of SEQ ID NO:2, or nucleotides 5620-7533 of SEQ ID NO:3, or naturally occurring mutants thereof.
In another aspect, the invention features a method of localizing the origin of a porcine retroviral infection. The method includes:
contacting a target nucleic acid from the graft with a second sequence chosen from the group of: a sequence which can specifically hybridize to a porcine retroviral sequence; a sequence which can specifically hybridize to the sequence of SEQ ID NO:1 or its complement; a sequence which can specifically hybridize to the sequence of SEQ ID NO:2 or its complement; a sequence which can specifically hybridize to the sequence of SEQ ID NO:3 or its complement; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence which encodes a gag protein; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence from nucleotides 2452-4839 (e.g, from nucleotides 3112-4683) of SEQ ID NO:1, nucleotides 598-2169 (e.g, from nucleotides 598-10 2169) of SEQ ID NO:2, or nucleotides 585-2156 (e.g, from nucleotides 585-2156) of SEQ ID NO:3, or naturally occurring mutants thereof; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence which encodes a pol protein; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence from nucleotides 4871-8060 of SEQ ID NO:1, nucleotides 2320-4737 of SEQ ID NO:2, or nucleotides 2307-5741 of SEQ ID NO:3, or naturally occurring mutants thereof;
a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence which encodes a env protein; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence from nucleotides 2-1999 (e.g, from nucleotides 86-1999) of SEQ ID NO:1, nucleotides 4738-6722 (e.g, from nucleotides 4738-6722) of SEQ ID NO:2, or nucleotides 5620-7533 of SEQ ID NO:3, or naturally occurring mutants thereof; a swine or miniature swine retroviral nucleic acid; or a Tsukuba nucleic acid contacting a target nucleic acid from the recipient with a second sequence chosen from the group of: a sequence which can specifically hybridize to a porcine retroviral sequence; a sequence which can specifically hybridize to the sequence of SEQ ID NO:1 or its complement; a sequence which can specifically hybridize to the sequence of SEQ ID NO:2 or its complement; a sequence which can specifically hybridize to the sequence of SEQ ID NO:3 or its complement; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence which encodes a gag protein; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence from nucleotides 2452-4839 (e.g. from nucleotides 31124683) of SEQ ID NO:1, nucleotides 598-2169 (e.g, from nucleotides 598-2169) of SEQ ID NO:2, or nucleotides 585-2156 (e.g, from nucleotides 585-2156) of SEQ ID NO:3, or naturally occurring mutants thereof; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence which encodes a pol protein; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence from nucleotides 4871-8060 of SEQ ID NO:1, nucleotides 2320-4737 of SEQ ID NO:2, or nucleotides 2307-5741 of SEQ ID NO:3, or naturally occurring mutants thereof; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence which encodes a env protein; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence from nucleotides 2-1999 (e.g, from nucleotides 86-1999) of SEQ ID NO:1, nucleotides 4738-6722 (e.g, from nucleotides 4738-6722) of SEQ ID NO:2, or nucleotides 5620-7533 of SEQ ID NO:3, or naturally occurring mutants thereof; a swine or miniature swine retroviral nucleic acid; or a Tsukuba nucleic acid; hybridization to the nucleic acid from the graft correlates with the porcine retroviral infection in the graft; and hybridization to the nucleic acid from the recipient correlates with the porcine retroviral infection in the recipient.
In preferred embodiments, the target nucleic acid includes: genomic DNA, RNA or cDNA, e.g., cDNA made from an RNA template.
In a preferred embodiment: the second nucleic acid is a porcine retroviral sequence, probe or primer, e.g., as described herein, e.g., a Tsukuba-1 retroviral sequence; the second nucleic acid is a sequence of SEQ ID NO:1 or its complement, SEQ ID NO:2 or its complement, or SEQ ID NO:3 or its complement, or a fragment of the sequence or complement at least 10, 20, or 30, basepairs in length.
In preferred embodiments, the recipient is an animal, e.g., a miniature swine, a swine, a non-human primate, or a human.
In preferred embodiments, the graft is selected from the group consisting of: heart, lung, liver, bone marrow or kidney.
In preferred embodiments, the second nucleic acid has at least 60%, 70%, 72%, more preferably at least 85%, more preferably at least 90%, more preferably at least 95%, most preferably at least 98%, 99% or 100% sequence identity or homology with a sequence from SEQ ID NO:1 or its complement, SEQ ID NO:2 or its complement, or SEQ ID NO:3 or its complement.
In other preferred embodiments: the second nucleic acid is at least 10, more preferably at least 15, more preferably at least 20, most preferably at least 25, 30, 50, 100, 1000, 2000, 4000, 6000, or 8060 nucleotides in length; the nucleic acid is less than 15, more preferably less than 20, most preferably less than 25, 30, 50, 100, 1000, 2000, 4000, 6000, or 8060 nucleotides in length; the second nucleic acid is a full length retroviral genome.
In another aspect, the invention features a method of screening a cell, e.g., a cell having a disorder, e.g., a proliferative disorder, e.g., a tumor cell, e.g., a cancer cell, e.g., a lymphoma or a hepatocellular carcinoma, developing in a graft recipient, e.g., a xenograft, for the presence or expression of a porcine retrovirus or retroviral sequence. The method includes:
contacting a target nucleic acid from a tumor cell with a second sequence chosen from the group of: a sequence which can specifically hybridize to a porcine retroviral sequence; a sequence which can specifically hybridize to the sequence of SEQ ID.NO:1 or its complement; a sequence which can specifically hybridize to the sequence of SEQ ID NO:2 or its complement; a sequence which can specifically hybridize to the sequence of SEQ ID NO:3 or its complement; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence which encodes a gag protein; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence from nucleotides 2452-4839 (e.g, from nucleotides 3112-4683) of SEQ ID NO:1, nucleotides 598-2169 (e.g, from nucleotides 598-2169) of SEQ ID NO:2, or nucleotides 585-2156 (e.g, from nucleotides 585-2156) of SEQ ID NO:3, or naturally occurring mutants thereof; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence which encodes a pol protein; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence from nucleotides 4871-8060 of SEQ ID NO:1, nucleotides 2320-4737 of SEQ ID NO:2, or nucleotides 2307-5741 of SEQ ID NO:3, or naturally occurring mutants thereof; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence which encodes a env protein; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence from nucleotides 2-1999 (e.g, from nucleotides 86-1999) of SEQ ID NO:1, nucleotides 4738-6722 (e.g, from nucleotides 4738-6722) of SEQ ID NO:2, or nucleotides 5620-7533 of SEQ ID NO:3, or naturally occurring mutants thereof; a swine or miniature swine retroviral nucleic acid; or a Tsukuba nucleic acid, under conditions in which the sample and the nucleic acid sequence can hybridize, hybridization being indicative of the presence of the endogenous porcine retrovirus or retroviral sequence in the tumor cell.
In preferred embodiments, the target nucleic acid from a tumor cell includes: genomic DNA, RNA or cDNA, e.g., cDNA made from an RNA template.
In a preferred embodiment: the second nucleic acid is a porcine retroviral sequence, probe or primer, e.g., as described herein, e.g., a Tsukuba-1 retroviral sequence; the second nucleic acid is a sequence of SEQ ID NO:1 or its complement, SEQ ID NO:2 or complement, or SEQ ID NO:3 or its complement, or a fragment of the sequence or complement at least 10, 20, or 30, basepairs in length.
In preferred embodiments, the second nucleic acid has at least 60%, 70%, 72%, more preferably at least 85%, more preferably at least 90%, more preferably at least 95%, most preferably at least 98%, 99% or 100% sequence identity or homology with a sequence from SEQ ID NO:1 or its complement, SEQ ID NO:2 or its complement, or SEQ ID NO:3 or its complement.
In other preferred embodiments: the second nucleic acid is at least 10, more preferably at least 15, more preferably at least 20, most preferably at least 25, 30, 50, 100, 1000, 2000, 4000, 6000, or 8060 nucleotides in length; the nucleic acid is less than 15, more preferably less than 20, most preferably less than 25, 30, 50, 100, 1000, 2000, 4000, 6000, or 8060 nucleotides in length; the second nucleic acid is a full length retroviral genome.
In another aspect, the invention features a method of screening a human subject for the presence or expression of an endogenous porcine retrovirus or retroviral sequence comprising:
contacting a target nucleic acid derived from the human subject with a second sequence chosen from the group of: a sequence which can specifically hybridize to a porcine retroviral sequence; a sequence which can specifically hybridize to the sequence of SEQ ID NO:1 or its complement; a sequence which can specifically hybridize to the sequence of SEQ ID NO:2 or its complement; a sequence which can specifically hybridize to the sequence of SEQ ID NO:3 or its complement; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence which encodes a gag protein; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence from nucleotides 2452-4839 (e.g, from nucleotides 3112-4683) of SEQ ID NO:1, nucleotides 598-2169 (e.g, from nucleotides 598-2169) of SEQ ID NO:2, or nucleotides 585-2156 (e.g, from nucleotides 585-2156) of SEQ ID NO:3, or naturally occurring mutants thereof; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence which encodes a pol protein; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence from nucleotides 4871-8060 of SEQ ID NO:1, nucleotides 2320-4737 of SEQ ID NO:2, or nucleotides 2307-5741 of SEQ ID NO:3, or naturally occurring mutants thereof; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence which encodes a env protein; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence from nucleotides 2-1999 (e.g, from nucleotides 86-1999) of SEQ ID NO:1, nucleotides 4738-6722 (e.g, from nucleotides 4738-6722) of SEQ ID NO:2, or nucleotides 5620-7533 of SEQ ID NO:3, or naturally occurring mutants thereof; a swine or miniature swine retroviral nucleic acid; or a Tsukuba nucleic acid under conditions in which the sequences can hybridize, hybridization being indicative of the presence of the endogenous porcine retrovirus or retroviral sequence in the human subject.
In preferred embodiments, the target nucleic acid derived from a human subject is DNA, RNA or cDNA sample, nucleic acid from a blood sample or a tissue sample, e.g., a tissue biopsy sample.
In preferred embodiments, the human subject is a miniature swine or swine xenograft recipient, or a person who has come into contact with a miniature swine or swine xenograft recipient.
In preferred embodiments, the second nucleic acid has at least 60%, 70%, 72%, more preferably at least 85%, more preferably at least 90%, more preferably at least 95%, most preferably at least 98%, 99% or 100% sequence identity or homology with a sequence from SEQ ID NO:1 or its complement, SEQ ID NO:2 or its complement, or SEQ ID NO:3 or its complement.
In other preferred embodiments: the second nucleic acid is at least 10, more preferably at least 15, more preferably at least 20, most preferably at least 25, 30, 50, 100, 1000, 2000, 4000, 6000, or 8060 nucleotides in length; the nucleic acid is less than 15, more preferably less than 20, most preferably less than 25, 30, 50, 100, 1000, 2000, 4000, 6000, or 8060 nucleotides in length; the second nucleic acid is a full length retroviral genome.
In preferred embodiments: the recipient is tested for the presence of porcine retroviral sequences prior to implantation of swine or miniature swine tissue.
In another aspect, the invention features a method of screening for viral mutations which modulate, e.g., increase or decrease, susceptibility of a porcine retrovirus to an antiviral agent, e.g., an antiviral antibiotic. The method includes:
administering a treatment, e.g., an antiviral agent, e.g., an antiviral antibiotic;
isolating a putative mutant porcine retroviral strain;
determining a structure of the putative mutant retroviral strain; and
comparing the structure to SEQ ID NO:1 or its complement, SEQ ID NO:2 or its complement, or SEQ ID NO:3 or its complement.
In another aspect, the invention features a method of screening for viral mutations which modulate, e.g., increase or decrease, susceptibility of a porcine retrovirus to an antiviral agent, e.g., an antiviral antibiotic. The method includes:
growing the porcine retrovirus in a presence of a treatment, e.g., an antiviral agent, e.g., an antiviral antibiotic; and
determine the amount of porcine retroviral DNA synthesized by hybridizing the porcine retroviral DNA to a second sequence chosen from the group of: a sequence which can specifically hybridize to a porcine retroviral sequence; a sequence which can specifically hybridize to the sequence of SEQ ID NO:1 or its complement; a sequence which can specifically hybridize to the sequence of SEQ ID NO:2 or its complement; a sequence which can specifically hybridize to the sequence of SEQ ID NO:3 or its complement; a nucleic acid, of at least 10 consecutive nucleotides of sense or antisense sequence which encodes a gag protein; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence from nucleotides 2452-4839 (e.g, from nucleotides 3112-4683) of SEQ ID NO:1, nucleotides 598-2169 (e.g, from nucleotides 598-2169) of SEQ ID NO:2, or nucleotides 585-2156 (e.g, from nucleotides 585-2156) of SEQ ID NO:3, or naturally occurring mutants thereof; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence which encodes a pol protein; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence from nucleotides 4871-8060 of SEQ ID NO:1, nucleotides 2320-4737 of SEQ ID NO:2, or nucleotides 2307-5741 of SEQ ID NO:3, or naturally occurring mutants thereof; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence which encodes a env protein; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence from nucleotides 2-1999 (e.g, from nucleotides 86-1999) of SEQ ID NO:1, nucleotides 4738-6722 (e.g, from nucleotides 4738-6722) of SEQ ID NO:2, or nucleotides 5620-7533 of SEQ ID NO:3, or naturally occurring mutants thereof; a swine or miniature swine retroviral nucleic acid; or a Tsukuba nucleic acid.
In preferred embodiments, the method further includes amplifying the porcine retroviral nucleic acid with primers which specifically hybridize to the sequence of SEQ ID NO:1 or its complement, SEQ ID NO:2 or its complement, or SEQ ID NO:3 or its complement, e.g., by polymerase chain reaction quantitative DNA testing (PDQ).
In a preferred embodiment: the second nucleic acid is a Tsukuba-1 retroviral sequence, probe or primer, e.g., as described herein; the second nucleic acid is a porcine retroviral sequence, probe or primer, e.g., as described herein; the second nucleic acid is the sequence of SEQ ID NO:1 or its complement, SEQ ID NO:2 or its complement, or SEQ ID NO:3 or its complement.
In preferred embodiments, the second nucleic acid has at least 60%, 70%, 72%, more preferably at least 85%, more preferably at least 90%, more preferably at least 95%, most preferably at least 98%, 99% or 100% sequence identity or homology with a sequence from SEQ ID NO:1 or its complement, SEQ ID NO:2 or its complement, or SEQ ID NO:3 or its complement.
In other preferred embodiments: the second nucleic acid is at least 10, more preferably at least 15, more preferably at least 20, most preferably at least 25, 30, 50, 100, 1060, 2000, 4000, 6000, or 8060 nucleotides in length; the nucleic acid is less than 15, more preferably less than 20, most preferably less than 25, 30, 50, 100, 1000, 2000, 4000, 6000, or 8060 nucleotides in length; the second nucleic acid is a full length retroviral genome.
In another aspect, the invention features a method for screening a porcine-derived product for the presence or expression of a swine or miniature swine retrovirus or retroviral sequence, e.g., an endogenous miniature swine retrovirus. The method includes:
contacting a target nucleic acid from the porcine-derived product with a second sequence chosen from the group of: a sequence which can specifically hybridize to a porcine retroviral sequence; a sequence which can specifically hybridize to the sequence of SEQ ID NO:1 or its complement; a sequence which can specifically hybridize to the sequence of SEQ ID NO:2 or its complement; a sequence which can specifically hybridize to the sequence of SEQ ID NO:3 or its complement; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence which encodes a gag protein; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence from nucleotides 2452-4839 (e.g, from nucleotides 3112-4683) of SEQ ID NO:1, nucleotides 598-2169 (e.g, from nucleotides 598-2169) of SEQ ID NO:2, or nucleotides 585-2156 (e.g, from nucleotides 585-2156) of SEQ ID NO:3, or naturally occurring mutants thereof; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence which encodes a pol protein; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence from nucleotides 4871-8060 of SEQ ID NO:1, nucleotides 2320-4737, of SEQ ID NO:2, or nucleotides 2307-5741 of SEQ ID NO:3, or naturally occurring mutants thereof; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence which encodes a env protein; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence from nucleotides 2-1999 (e.g, from nucleotides 86-1999) of SEQ ID NO:1, nucleotides 4738-6722 (e.g, from nucleotides 4738-6722) of SEQ ID NO:2, or nucleotides 5620-7533 of SEQ ID NO:3, or naturally occurring mutants thereof; a swine or miniature swine retroviral nucleic acid; or a Tsukuba nucleic acid, under conditions in which hybridization can occur, hybridization being indicative of the presence or expression of an endogenous miniature swine or swine retrovirus or retroviral sequences in the porcine-derived product.
In preferred embodiments the product is: a protein product, e.g., insulin; a food product; or a cellular transplant, e.g., a swine or miniature swine cell which is to be transplanted into a host, e.g., a swine or miniature swine cell which is genetically engineered to express a desired product.
In preferred embodiments, the method further includes amplifying the target nucleic acid with primers which specifically hybridize to the sequence of SEQ ID NO:1 or its complement, SEQ ID NO:2 or its complement, or SEQ ID NO:3 or its complement.
In other preferred embodiments, the target nucleic acid is: DNA; RNA; or cDNA.
In preferred embodiments, the second nucleic acid has at least 60%, 70%, 72%, more preferably at least 85%, more preferably at least 90%, more preferably at least 95%, most preferably at least 98%, 99% or 100% sequence identity or homology with a sequence from SEQ ID NO:1 or its complement, SEQ ID NO:2 or its complement, or SEQ ID NO:3 or its complement.
In other preferred embodiments: the second nucleic acid is at least 10, more preferably at least 15, more preferably at least 20, most preferably at least 25, 30, 50, 100, 1000, 2000, 4000, 6000, or 8060 nucleotides in length; the nucleic acid is less than 15, more preferably less than 20, most preferably less than 25, 30, 50, 100, 1000, 2000, 4000, 6000, or 8060 nucleotides in length; the second nucleic acid is a full length retroviral genome.
In another aspect, the invention features a transgenic miniature swine or swine having a transgenic element, e.g., a base change, e.g., a change from A to G, or an insertion or a deletion of one or more nucleotides at an endogenous porcine retroviral insertion site, e.g., a retroviral insertion which corresponds to the retroviral genome of SEQ ID NO:1 or its complement, SEQ ID NO:2 or its complement, or SEQ ID NO:3 or its complement.
In preferred embodiments, the transgenic element is a knockout, e.g., a deletion, insertion or a translocation, of one or more nucleic acids, which alters the activity of the endogenous porcine retrovirus.
In another aspect, the invention features a method of inhibiting expression of an endogenous porcine retrovirus, including: inserting a mutation, e.g. a deletion into the endogenous retrovirus.
In preferred embodiments, the endogenous porcine retrovirus is inactivated.
In preferred embodiments, the mutation can be a point mutation, an inversion, translocation or a deletion of one or more nucleotides of SEQ ID NO:1 or its complement, SEQ ID NO:2 or its complement, or SEQ ID NO:3 or its complement.
In another aspect, the invention features a method of detecting a recombinant virus or other pathogen, e.g., a protozoa or fungi. The method includes:
providing a pathogen having porcine retroviral sequence, and
determining if the pathogen includes non-porcine retroviral sequence, the presence of non-porcine retroviral sequence being indicative of viral recombination.
In preferred embodiments, the method further includes determining the structure of a retrovirus by comparing the retrovirus sequence with sequence of SEQ ID NO:1 or its complement, SEQ ID NO:2 or its complement, or SEQ ID NO:3 or its complement, a difference being indicative of viral recombination.
In preferred embodiments, the method further includes comparing the structure of the retrovirus with a human retroviral sequence, e.g., HTLV1, HIV1, or HIV2, a similarity in structure being indicative of viral recombination.
In another aspect, the invention features a method of determining the copy number, size, or completeness of a porcine retrovirus or retroviral sequence , e.g., in the genome of a donor, recipient or a graft. The method includes:
contacting a target nucleic acid from the donor, recipient or a graft, with a second sequence chosen from the group of: a sequence which can specifically hybridize to a porcine retroviral sequence; a sequence which can specifically hybridize to the sequence of SEQ ID NO:1 or its complement; a sequence which can specifically hybridize to the sequence of SEQ ID NO:2 or its complement; a sequence which can specifically hybridize to the sequence of SEQ ID NO:3 or its complement; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence which encodes a gag protein; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence from nucleotides 2452-4839 (e.g, from nucleotides 3112-4683) of SEQ ID NO:1, nucleotides 598-2169 (e.g, from nucleotides 598-2169):of SEQ ID NO:2, or nucleotides 585-2156 (e.g, from nucleotides 585-2156) of SEQ ID NO:3, or naturally occurring mutants thereof;
a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence which encodes a pol protein; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence from nucleotides 4871-8060 of SEQ ID NO:1, nucleotides 2320-4737 of SEQ ID NO:2, or nucleotides 2307-5741 of SEQ ID NO:3, or naturally occurring mutants thereof;
a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence which encodes a env protein; a nucleic acid of at least 10 consecutive nucleotides of sense or antisense sequence from nucleotides 2-1999 (e.g, from nucleotides 86-1999) of SEQ ID NO:1, nucleotides 4738-6722 (e.g, from nucleotides 4738-6722) of SEQ ID NO:2, or nucleotides 5620-7533 of SEQ ID NO:3, or naturally occurring mutants thereof; a swine or miniature swine retroviral nucleic acid; or a Tsukuba nucleic acid.
In preferred embodiments, the method further includes amplifying the porcine retroviral nucleic acid with primers which specifically hybridize to the sequence of SEQ ID NO:1 or its complement, SEQ ID NO:2 or its complement, or SEQ ID NO:3 or its complement, e.g., by polymerase chain reaction quantitative DNA testing (PDQ) or nested PCR.
In preferred embodiments, the target nucleic acid includes: genomic DNA isolated from a miniature swine; RNA or cDNA, e.g., cDNA made from an RNA template, isolated from a miniature swine; DNA, RNA or cDNA, e.g., cDNA made from an RNA template, isolated from a miniature swine organ, e.g., a kidney; RNA, DNA or cDNA, e.g., cDNA made from an RNA template, isolated from a miniature swine organ which has been transplanted into a organ recipient, e.g., a xenogeneic recipient, e.g., a primate, e.g., a human.
In preferred embodiments, the target nucleic acid includes: genomic DNA isolated from a swine; RNA or cDNA, e.g., cDNA made from an RNA template, isolated from a swine; DNA, RNA or cDNA, e.g., cDNA made from an RNA template, isolated from a swine organ, e.g., a kidney; RNA, DNA or cDNA, e.g., cDNA made from an RNA template, isolated from a swine organ which has been transplanted into a organ recipient, e.g., a xenogeneic recipient, e.g., a primate, e.g., a human.
In preferred embodiments, the second nucleic acid has at least 60%, 70%, 72%, more preferably at least 85%, more preferably at least 90%, more preferably at least 95%, most preferably at least 98%, 99% or 100% sequence identity or homology with a sequence from SEQ ID NO:1 or its complement, SEQ ID NO:2 or its complement, or SEQ ID NO:3 or its complement.
In other preferred embodiments: the second nucleic acid is at least 10, more preferably at least 15, more preferably at least 20, most preferably at least 25, 30, 50, 100, 1000, 2000, 4000, 6000, or 8060 nucleotides in length; the nucleic acid is less than 15, more preferably less than 20, most preferably less than 25, 30, 50, 100, 1000, 2000, 4000, 6000, or 8060 nucleotides in length; the second nucleic acid is a full length retroviral genome.
In another aspect, the invention features a method for screening a tissue, e.g., a cellular or tissue transplant, e.g., a xenograft, or a tissue from a graft recipient, for the presence or expression of a swine or a miniature swine retroviral sequence, e.g., an endogenous miniature swine retrovirus. The method includes: contacting a tissue sample with an antibody specific for a retroviral protein, e.g., an anti-gag, pol, or env antibody, and thereby determining if the sequence is present or expressed.
In preferred embodiments the protein is encoded by a sequence from: the sequence of SEQ ID NO:1 or its complement, SEQ ID NO:2 or its complement, or SEQ ID NO:3 or its complement.
In preferred embodiments, the tissue is selected from the group consisting of: heart, lung, liver, bone marrow, kidney, brain cells, neural tissue, pancreas or pancreatic cells, thymus, or intestinal tissue.
A xe2x80x9cpurified preparationxe2x80x9d or a xe2x80x9csubstantially pure preparationxe2x80x9d of a polypeptide as used herein, means a polypeptide which is free from one or more other proteins, lipids, and nucleic acids with which it naturally occurs. Preferably, the polypeptide, is also separated from substances which are used to purify it, e.g., antibodies or gel matrix, such as polyacrylamide. Preferably, the polypeptide constitutes at least 10, 20, 50 70, 80 or 95% dry weight of the purified preparation. Preferably, the preparation contains: sufficient polypeptide to allow protein sequencing; at least 1, 10, or 100 xcexcg of the polypeptide; at least 1, 10, or 100 mg of the polypeptide.
Specifically hybridize, as used herein, means that a nucleic acid hybridizes to a target sequence with substantially greater degree than it does to other sequences in a reaction mixture. By substantially greater means a difference sufficient to determine if the target sequence is present in the mixture.
A xe2x80x9ctreatmentxe2x80x9d, as used herein, includes any therapeutic treatment, e.g., the administration of a therapeutic agent or substance, e.g., a drug or irradiation.
A xe2x80x9cpurified preparation of nucleic acidxe2x80x9d, is a nucleic acid which is one or both of: not immediately contiguous with one or both of the coding sequences with which it is immediately contiguous (i.e., one at the 5xe2x80x2 end and one at the 3xe2x80x2 end) in the naturally-occurring genome of the organism from which the nucleic acid is derived; or which is substantially free of a nucleic acid sequence or protein with which it occurs in the organism from which the nucleic acid is derived. The term includes, for example, a recombinant DNA which is incorporated into a vector, e.g., into an autonomously replicating plasmid or virus, or into the genomic DNA of a prokaryote or eukaryote, or which exists as a separate molecule (e.g., a cDNA or a genomic DNA fragment produced by PCR or restriction endonuclease treatment) independent of other DNA sequences. Substantially pure DNA also includes a recombinant DNA which is part of a hybrid gene encoding additional sequences. A purified retroviral genome is a nucleic acid which is substantially free of host nucleic acid or viral protein.
xe2x80x9cHomologousxe2x80x9d, as used herein, refers to the sequence similarity between two polypeptide molecules or between two nucleic acid molecules. When a position in both of the two compared sequences is occupied by the same amino acid or base monomer subunit, e.g., if a position in each of two DNA molecules is occupied by adenine, then the molecules are homologous at that position. The percent of homology between two sequences is a function of the number of matching or homologous positions shared by the two sequences divided by the number of positions comparedxc3x97100. For example, if 6 of 10, of the positions in two sequences are matched or homologous then the two sequences are 60% homologous. By way of example, the DNA sequences ATTGCC and TATGGC share 50% homology. Generally, a comparison is made when two sequences are aligned to give maximum homology. The term sequence identity has substantially the same meaning.
The term xe2x80x9cprovirusxe2x80x9d or xe2x80x9cendogenous retrovirus,xe2x80x9d as used herein, refers to an integrated form of the retrovirus.
The terms xe2x80x9cpeptidesxe2x80x9d, xe2x80x9cproteinsxe2x80x9d, and xe2x80x9cpolypeptidesxe2x80x9d are used interchangeably herein.
As used herein, the term xe2x80x9ctransgenic elementxe2x80x9d means a nucleic acid sequence, which is partly or entirely heterologous, i.e., foreign, to the animal or cell into which it is introduced but which is designed to be inserted, or is inserted, into the animal""s genome in such a way as to alter the genome of the cell into which it is inserted. The term includes elements which cause a change in the sequence, or in the ability to be activated, of an endogenous retroviral sequence. Examples of transgenic elements include those which result in changes, e.g., substitutions (e.g., A for G), insertions or deletions of an endogenous retroviral sequence (or flanking regions) which result in inhibition of activation or misexpression of a retroviral product.
As used herein, the term xe2x80x9ctransgenic cellxe2x80x9d refers to a cell containing a transgenic element.
As used herein, a xe2x80x9ctransgenic animalxe2x80x9d is any animal in which one or more, and preferably essentially all, of the cells of the animal includes a transgenic element. The transgenic element can be introduced into the cell, directly or indirectly by introduction into a precursor of the cell, by way of deliberate genetic manipulation, such as by microinjection. This molecule may be integrated within a chromosome, or it may be extrachromosomally replicating DNA.
As described herein, one aspect of the invention features a pure (or recombinant) nucleic acid which includes a miniature swine (or swine) retroviral genome or fragment thereof, e.g., nucleotide sequence encoding a gag-pol or env polypeptide, and/or equivalents of such nucleic acids. The term xe2x80x9cnucleic acidxe2x80x9d, as used herein, can include fragments and equivalents. The term xe2x80x9cequivalentxe2x80x9d refers to nucleotide sequences encoding functionally equivalent polypeptides or functionally equivalent polypeptides which, for example, retain the ability to react with an antibody specific for a gag-pol or env polypeptide. Equivalent nucleotide sequences will include sequences that differ by one or more nucleotide substitutions, additions or deletions, such as allelic variants, and will, therefore, include sequences that differ from the nucleotide sequence of gag, pol, or env shown in herein due to the degeneracy of the genetic code.
xe2x80x9cMisexpressionxe2x80x9d, as used herein, refers to a non-wild type pattern of gene expression, e.g.,porcine retroviral, e.g., Tsukuba-1 gene expression, e.g., gag, pol or env gene expression. It includes: expression at non-wild type levels, i.e., over or under expression; a pattern of expression that differs from wild type in terms of the time or stage at which the gene is expressed, e.g., increased or decreased expression (as compared with wild type) at a predetermined developmental period or stage; a pattern of expression that differs from wild type in terms of decreased expression (as compared with wild type) in a predetermined cell type or tissue type; a pattern of expression that differs from wild type in terms of the splicing, size, amino acid sequence, post-translational modification, stability, or biological activity of the expressed ,porcine retroviral, e.g.,Tsukuba-1, polypeptides; a pattern of expression that differs from wild type in terms of the effect of an environmental stimulus or extracellular stimulus on expression of the porcine retroviral, e.g., Tsukuba-1 genes, e.g., a pattern of increased or decreased expression (as compared with wild type) in the presence of an increase or decrease in the strength of the stimulus.
Methods of the invention can be used with swine or miniature swine.
Endogenous retrovirus is a potential source of infection not always susceptible to conventional breeding practices. Many proviruses are defective and unable to replicate. Provirus, if intact, can be activated by certain stimuli and then initiate viral replication using the host""s cellular mechanisms. Retroviral infection will often not harm the host cell. However, replication of virus may result in viremia, malignant transformation (e.g., via insertion of retroviral oncogenes), degeneration, or other insertional effects (e.g., gene inactivation). The effects of such infection may not emerge for many years. The spectrum of behavior of active lentiviral infection in humans is well described relative to HIV. These include AIDS, unusual infections and tumors, recombinant and other viruses, and antigenic variation which may prevent the generation of protective immunity by the infected host.
Screening of animals will allow elimination of donors with active replication of known viruses. Inactive proviruses can be detected with genetic probes and removed or inactivated. These novel approaches will allow the identification and elimination of potential human pathogens derived from swine in a manner not possible in the outbred human organ donor population and, thus, will be important to the development of human xenotransplantation.
The porcine retroviral sequences of the invention are also useful as diagnostic probes to detect activation of endogenous porcine retroviruses following transplantation and xenotransplantation of organs derived from swine or miniature swine. The porcine retroviral sequences of the invention also provide diagnostic tools necessary to assess the risks associated with transplantation of organs from swine or miniature swine into human recipients. These sequences are also useful for the longitudinal evaluation of retroviral activation in the human recipient of miniature swine-derived organs.
The practice of the present invention will employ, unless otherwise indicated, conventional techniques of cell biology, cell culture, molecular biology, transgenic biology, microbiology, recombinant DNA, and immunology, which are within the skill of the art. Such techniques are described in the literature. See, for example, Molecular Cloning A Laboratory Manual, 2nd Ed., ed. by Sambrook, Fritsch and Maniatis (Cold Spring Harbor Laboratory Press: 1989); DNA Cloning, Volumes I and II (D. N. Glover ed., 1985); Oligonucleotide Synthesis (M. J. Gait ed., 1984); Mullis et al. U.S. Pat. No. 4,683,195; Nucleic Acid Hybridization (B. D. Hames and S. J. Higgins eds. 1984); Transcription And Translation (B. D. Hames and S. J. Higgins eds. 1984); Culture Of Animal Cells (R. I. Freshney, Alan R. Liss, Inc., 1987); Immobilized Cells And Enzymes (IRL Press, 1986); B. Perbal, A Practical Guide To Molecular Cloning (1984); the treatise, Methods In Enzymology (Academic Press, Inc., N.Y.); Gene Transfer Vectors For Mammalian Cells (J. H. Miller and M. P. Calos eds., 1987, Cold Spring Harbor Laboratory); Methods In Enzymology, Vols. 154 and 155 (Wu et al. eds.), Immunochemical Methods In Cell And Molecular Biology (Mayer and Walker, eds., Academic Press, London, 1987); Handbook Of Experimental Immunology, Volumes I-IV (D. M. Weir and C. C. Blackwell, eds., 1986); Manipulating the Mouse Embryo, (Cold Spring Harbor Laboratory Press, Cold Spring Harbor, N.Y., 1986).
Although methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present invention, the preferred methods and materials are described below. All publications mentioned herein are incorporated by reference. In addition, the materials, methods, and examples are illustrative only and not intended to be limiting.